1. Field of the Invention
The subject invention generally relates to transferring data within and between active computer applications and, more particularly, visually assisting operators in making such transfers between simultaneously active applications.
2. Description of the Prior Art
The need to transfer information between different computer application programs and between files within the same program has grown in importance along with the development of the capability to simultaneously display and access multiple files and application programs on a single computer screen through the use of windows or viewports. Each application displayed within a window can be initiated, accessed, changed, saved, closed and exited independently of events occurring within other concurrently displayed windows. The operator may thereby view and manipulate data within and between multiple sources without the inconvenience and loss of time involved in closing and exiting one application in order to access another.
An additional benefit of multiple, simultaneously active application programs is the possibility of obtaining data stored or calculated by one application program and transferring it directly to another. For example, one window can calculate and display the results of a spreadsheet calculation which is needed in a simultaneously displayed full screen editing program. The desired transfer of information can be accomplished through a "cut and paste" operation which involves either deleting or copying the data from one application (both of which functions may be referred to as "cutting") and writing that data (sometimes referred to as a "pasting" function) into another application.
Certain text editors perform this operation on a basic level by allowing the operator to write a specified number of lines into a temporary system buffer or another file using a GET function and then to later retrieve those lines during the same or later session with the text editor by using a PUT function. However, such editors are relatively primitive since they do not show the operator the contents of the temporary buffer/file, thus failing to provide a full screen interface to the operator who has no readily accessible visual concept of what is occurring during the cut and paste operation. Moreover, this type of text editor is generally designed only to transfer data between files within the same program rather than between different programs. A more detailed explanation of the functioning of such text editors is provided in "VM/SP System Product Editor Operator's Guide," International Business Machines Corp., Manual No. SC24-5221-2.
Certain applications do support cut and paste operations between serially executing programs as well as within applications. A transient data storage buffer area, known as a "clipboard", is used to temporarily store manually marked data from one window of the display screen until it is pasted into a location in another window specified by positioning of the screen cursor at a point within the latter window. Details of such an application are discussed in two books entitled "Microsoft Windows Operators Guide" and "Microsoft Windows Operating Environment" which are both available from Microsoft Corporation, Bellevue, Wash.
Although the "clipboard" type of cut and paste operation accomplishes the end goal of transferring information between concurrently active applications, it does so without providing a consistent operator/screen interface and in a manner which is not particularly operator-friendly. For example, once data has been marked and stored on the "clipboard", the window screen display, in a case involving copying rather than deletion, remains visually unchanged from its appearance prior to the "cut" without providing the operator any spatial references while he seeks to reposition the data at its destination location unless he refers back to the data source location. In a case where source data is meant to be deleted, that deletion occurs prior to reinsertion at the data destination location, thereby exacerbating the operator's problems since he loses totally the ability even to refresh his memory due to the complete disappearance of the source data from the computer display screen once a "cut" has been initiated. Thus, he must rely on imagination to picture important parameters of deleted information such as its width, size and centering, making appropriate placement of the data to be pasted much more difficult, time-consuming and inconvenient. In certain programs, when a deletion occurs, this problem is further compounded by automatic reformatting of the text remaining on the computer display screen at the data source location. Finally, regardless of whether a delete or copy type of cut and paste operation is undertaken, the operator is generally offered no visual assistance from the screen to indicate either that such an operation is in progress or how far it has progressed. The absence of a friendly and informative operator interface diminishes the value of existing methods of cutting and pasting data both within and between applications.